ABSTRACT: BACKGROUND: Retracing the genetic histories of the descendant
populations of the Slave Trade (16th-19th centuries) is particularly
challenging due to the diversity of African ethnic groups involved and the
different hybridisation processes with Europeans and Amerindians, which have
blurred their original genetic inheritances. The Noir Marron in French
Guiana are the direct descendants of maroons who escaped from Dutch
plantations in the current day Surinam. They represent an original ethnic
group with a highly blended culture. Uniparental markers (mtDNA and NRY)
coupled with HTLV-1 sequences (env and LTR) were studied to establish the
genetic relationships linking them to African American and African
populations. RESULTS: All genetic systems presented a high conservation of
the African gene pool (African ancestry: mtDNA = 99.3%; NRY = 97.6%; HTLV-1
env = 20/23; HTLV-1 LTR = 6/8). Neither founder effect nor genetic drift was
detected and the genetic diversity is within a range commonly observed in
Africa. Higher genetic similarities were observed with the populations
inhabiting the Bight of Benin (from Ivory Coast to Benin). Other ancestries
were identified but they presented an interesting sex-bias. Whilst male
origins spread throughout the north of the bight (from Benin to Senegal),
female origins were spread throughout the south (from the Ivory Coast to
Angola). CONCLUSIONS: The Noir Marron are unique in having conserved their
African genetic ancestry, despite major cultural exchanges with Amerindians
and Europeans through inhabiting the same region for four centuries. Their
maroon identity and the important number of slaves deported in this region
have maintained the original African diversity. All these characteristics
permit to identify a major origin located in the former region of the Gold
Coast and the Bight of Benin; regions highly impacted by slavery, from which
goes a sex-biased longitudinal gradient of ancestry.